Multi-layer heating apparatus

ABSTRACT

A multi-layer heating apparatus having a heating unit ( 1 ) provided on the bottom of a cooking device ( 5 ), and an accumulator ( 2 ) attached to the heating unit ( 1 ). The heating unit ( 1 ) is filled with a liquid that needed to be heated and set above of a heat source ( 7 ). The heating apparatus is characterized in that at least one air conduit tube ( 3 ) is provided on the top of the heating unit ( 1 ) for leading the exhaust gas out. The air conduit tube ( 3 ) and multi layers hot water pipes ( 121 ) provided in the heating unit ( 1 ) served as a heating means, which can heat up the liquid efficiently.

FIELD OF THE INVENTION

The present invention relates to a multi-layer heating apparatus, more specifically to be mounted on a steam cooker or a deep fryer.

DESCRIPTION OF PRIOR ART

Steaming is a cooking method that utilizing extreme hot steam, generated by heating water with a burner provided under, to heat the food. Steaming is considered as a healthy way to cook the food as it preserves the nutrition within the food and keeps the meal in low fat. However, steaming consumes more energy comparing to other method because most of hot steam is expelled outside the cooker after passing the food with huge amount of heat remains therein. Through the years, inventions have been disclosed for improving the efficiency of the steam cooker, such as the cited document 1, U.S. Pat. No. 6,098,527, entitled “Structure of a steaming apparatus”, invented by the very same inventor of the present invention. The cited document 1 teaches a steam cooker having a water boiler and a burner placed under. The water boiler composed of an inner and outer channel with multiple pipes provided therein. The lateral walls of the inner channel and pipes can transfer the heat, reducing the boiling time of the water. Further, the boiler is sealed by a pressure-tight cover having tubes to eject steam. The temperature inside the cooker is increased as the pressure rises, with tubes eject steam toward the food, thus, the cooking time is reduced evidently.

Even though the device disclosed above increases the efficiency, the gas produced by the burner, however, is led toward the outside directly through a vent line provided between the inner and outer channel. The gas contains huge amount of heat and is completely wasted. Therefore, to use the heat from the gas combining the structure disclosed previously to improve further the efficiency of the steam cooker has become the main objective of the present invention.

SUMMARY OF THE INVENTION

To achieve above-identified object, a multi-layer heating apparatus can be realized by comprising a heating unit, an accumulator provided outside of the heating apparatus and linked to the heating unit for reserving and refilling liquid. The liquid is provided on a top of the heating unit, and a heating source is provided on a bottom thereof, wherein at least one air conduit tube is attached to an end of the top of the heating unit; said air conduit tube extends to an outside of the heating unit and attaches to a fume vent; the fume vent extends upwardly along a side wall of the apparatus and having its terminal set on the top of the apparatus.

At least one through hole is provided throughout said air conduit tube for transferring liquid, and a plurality of concavities are provided on a surface of said air conduit tube. The concavities are spaced with each other by a predetermined distance and arranged in pluralities of rows; said rows are arranged in a staggered formation.

An orifice is provided on a bottom of said fume vent for increasing the convection. The heating unit consists of a casing, an inner casing, which is disposed in the casing, having a plurality of hot water tubes provided horizontally therein, an inlet tube provided between said casing and the accumulator, and at least one outlet tube connected to the casing.

Said casing comprises a square hollow portion and a tapered opening attached to a top of said square portion. The bottom portion of said square portion is coupled to a bottom of the inner casing and a top of said tapered opening is coupled to an inner wall of the heating apparatus.

The inlet tube and said tapered opening are joined by a first relief pipe. A second relief pipe penetrates a side wall of an upper portion of the heating unit and links to the accumulator.

The hot water tubes are arranged in pluralities layers; each layer including a plurality of tube spaced by a predetermined distance, and the tubes of one layer are perpendicular with tubes of a lower layer.

COMPARISON WITH PRIOR ART

The advantages of the present invention are listed as following:

-   -   1. The employment of the air conduit tube not only the tube body         can be an additional source to heat the water, but also the hot         gas running through, that used to be wasted can be recycled to         heat the water, reducing the boiling time by half and         consumption of the fuel.     -   2. The apparatus can function efficiently under normal condition         and can be applied to variable cooking means; i.e. steam cooker         or deep fryer etc, with wild range of applications.

BRIEF DESCRIPTION OF DRAWINGS

FIG. 1 is an illustrative view of a preferred embodiment of the present invention.

FIG. 2 is an exploded view of the present invention.

FIG. 3 is a cross sectional view of the present invention along the line X-X for showing the operation of the heating apparatus and the fume vent.

FIG. 4 is another cross sectional view of the present invention along the lien Y-Y for illustrating the circulation of the water of the heating apparatus.

FIG. 5 is a cross sectional view of the present invention when employed in a device.

FIG. 6 is another sectional view of FIG. 5 from the same perspective as FIG. 4.

FIG. 7 is an illustrative view showing an application of the present invention installed on a steam cooker.

FIG. 8 is an illustrative view showing another application of the present invention installed on a deep fryer.

DETAIL DESCRIPTION OF PREFERRED EMBODIMENTS

The preferred embodiments of the present invention are described in detail hereinafter according to the appended drawings.

As shown in FIGS. 1-3, a multi-layer heating apparatus can be realized by comprising a heating unit (1), an accumulator (2) provided externally and attached to the heating unit (1) for supplying or refilling the liquid (water or oil) that needs to be heated. The liquid (6) required to be heated is placed on a top of the heating unit (1), and a heating source (7) can be provided on a bottom thereof. As the liquid contained in said accumulator can be either water or oil, the claimed heating apparatus can be applied to variable cooking means, i.e. steam cabinet, pasta cooker or even deep fryer.

At least one air conduit tube (3) is provided on an upper portion of the heating unit (1) for leading the gas produced during the heating process. Said tube (3) is extending toward the outside of the heating unit (1) by passing through the outer wall thereof and connects to a fume vent (4). The fume vent (4), as illustrated in FIGS. 5 and 6, extends upwardly along a side wall of a cooking device (5) which carried the heating unit (1) and having its terminal (51) set on the top of the device (5).

Referring to FIGS. 2-4, said air conduit tube (3) is preferably set on the top of the heating unit (1), either contacting directly or spaced by a predetermined distance; at least one through hole (31) is defined on the wall of said air conduit tube (3) for transferring liquid. The through hole (31) is set perpendicular to the flow direction of the liquid, and a diameter thereof is smaller than the air conduit tube (3).

Pluralities concavities (32) are provided on a surface of said air conduit tube (3). The concavities (32) are spaced with each other by a predetermined distance and arranged in pluralities of rows, and said rows are arranged in a staggered formation. The concavities (32) create additional heating surfaces, and with the shape to slow the flow rate, the temperature of the tube body is raised for heating the liquid above more efficiently.

FIG. 2 showing pluralities of holes (113) are set on the outer side wall of the heating unit (1). Said holes (113) allow the air conduit tubes (3) to pass and connect with the fume vent (4). At least one orifice (41) is provided on a lower section of said fume vent (4), where closer the heating unit (1) is preferable for introducing the cool air into the vent (4) and increasing the convection.

FIG. 5 illustrates a partial sectional view of the vent (4). The fume vent (4) is consisted of a metallic inner tube (42) and an outer insulation layer (43) covering said inner tube (42) in order to prevent the staff be harmed by the hot air whether the fume vent (4) is concealed or exposed to the cooking device (5).

Referring to FIGS. 4 and 6, said heating unit (1) consists of an outer casing (11), an inner casing (12), which is set within the outer casing (11), having a plurality of hot water tubes (121) provided horizontally therein, an inlet tube (13) provided between said outer casing (11) and the accumulator (2), and at least one outlet tube (14) connected to the outer casing (11). Said outer casing (11) comprises a square hollow portion (111) and a tapered opening (112) attached to a top of said square portion (111). Although the hollow portion (111) is defined to have a square shape, a cylindrical shaped is also allowed. The bottom portion of said hollow portion (111) is coupled to a bottom of the inner casing (12) and a top of said tapered opening (112) is coupled to an inner wall of the heating apparatus.

The inlet tube (13) and said tapered opening (112) are joined by a first relief pipe (15) to balance the pressure of the accumulator (2). An upper opening of the first relief pipe (15) should be higher than a liquid surface (6). Functioning as communication tube, the liquid inside first relief pipe (15) is automatically delivered to the heating unit (1) as the liquid surface (6) drops.

A second relief pipe (16), for relieving the internal pressure of the cooking device (5), is penetrating a side wall of an upper portion of the heating unit (1) and joins to the accumulator (2).

Said hot water tubes (121) are arranged in pluralities layers, and each layer consists of a plurality of tubes (121) spaced by a predetermined distance. As shown in FIGS. 3 and 4, the tubes of one layer are perpendicular with tubes of a lower layer, which means that hot water tubes (121) of each odd layer (layer 1, 3, 5 etc.) are arranged in a same fashion while hot water tubes (121) of each even layer (layer 2, 4, 6 etc.) are arranged in the same fashion.

The claimed heating apparatus can be applied to variable cooking means. FIGS. 7 and 8 demonstrate two possible applications of the apparatus. FIG. 7 shows the cooking device (5), which the partial view thereof has been shown in FIGS. 5 and 6 is a steam cabinet, for steam cooking dumpling or steamed bun, while FIG. 8 showing the cooking device (5) as a deep fryer, commonly utilized in fast food restaurant for frying chicken, fries or chips. Referring to FIG. 5, the heat source (7) heats up the liquid (6) inside the heating unit (1). The liquid (6) can be either water or oil, as the apparatus can be used with steam cabinet or deep fryer.

The embodiments shown and described herein are to be considered only as illustrative. As the heating apparatus can also be used in a pasta cooker, a water heater or even steam generator, it will be apparent that various applications may be made without departing from the spirit and scope of the invention. 

1. A multi-layer heating apparatus comprising a heating unit (1), an accumulator (2) provided outside of the heating apparatus and linked to the heating unit for reserving and refilling liquid; a liquid to be heated is provided on a top of the heating unit, and a heating source is provided on a bottom thereof, wherein At least one air conduit tube (3) is provided on an upper portion of the heating unit (1); an end thereof joins a side of the heating unit (1) and another end extends to an opposite side throughout the heating unit (1) and attaches to a fume vent (4); the fume vent is set extending upwardly along a side wall of the apparatus and having its terminal set on the top of the apparatus.
 2. The multi-layer heating apparatus of claim 1, wherein at least one through hole (31) is provided throughout said air conduit tube (3) for transferring liquid.
 3. The multi-layer heating apparatus of claim 1, wherein a plurality of concavities (32) are provided on a surface of said air conduit tube.
 4. The multi-layer heating apparatus of claim 3, wherein said concavities (32) are spaced with each other by a predetermined distance and arranged in pluralities of rows; said rows are arranged in a staggered formation.
 5. The multi-layer heating apparatus of claim 1, wherein an orifice (41) is provided on a lower section of said fume vent (4) for increasing air convection.
 6. The multi-layer heating apparatus of claim 1, wherein said heating unit (1) including an outer casing (11), an inner casing (12), which is disposed in the outer casing (11), having a plurality of hot water tubes (121) provided horizontally therein, an inlet tube (13) provided between said outer casing (11) and the accumulator (2), and at least one outlet tube (14) connected to the outer casing (11).
 7. The multi-layer heating apparatus of claim 6, wherein said outer casing (11) comprising a square hollow portion (111) and a tapered opening (112) attached to a top of said square portion (111); a bottom of said square portion (111) is coupled to a bottom of the inner casing (12) and a top of said tapered opening (112) is coupled to an inner wall of the heating apparatus.
 8. The multi-layer heating apparatus of claim 7, wherein said inlet tube (13) and said tapered opening (112) are joined by a first relief pipe (15).
 9. The multi-layer heating apparatus of claim 1, wherein a second relief pipe (16) penetrates a side wall of an upper portion of the heating unit (1) and links to the accumulator (2).
 10. The multi-layer heating apparatus of claim 6, wherein said hot water tubes (121) are arranged in pluralities layers; each layer including a plurality of tube spaced by a predetermined distance, and the tubes of one layer are perpendicular with tubes of a lower layer. 